Well, 12.5 is 25/2.
[tex]\frac { 25 }{ 2 } \times n=52\\ \\ \frac { 2 }{ 25 } \times \frac { 25 }{ 2 } \times n=52\times \frac { 2 }{ 25 } \\ \\ \therefore \quad n=\frac { 104 }{ 25 } =\frac { 100 }{ 25 } +\frac { 4 }{ 25 } =4+\frac { 4 }{ 25 } \\ \\ \therefore \quad n=4.00+0.16=4.16[/tex]
